Silicone-impregnated surfaces suitable for ironing



Patented Apr. 14, 1953 SILI'CONE -IMPREGNATED- SURFACES. SUITABLE'FORIRONING 'Ehoma's J1 Rasmussen, Schenectady, N; K, assignorto GeneralElectric Company, acorporaztionwof NewYoi-ki NoDrawing; ApplieaticinApriLIQ,19491.,

Serial No. 88,491;

1 Claim.

I 1 This invention relates to a method of treating flatirons and similar ironing appliances having metallic ironing surfaces, andiarticles of: manufacturewhich can be used for effecting treatment either ironing surfaces of such flatirons In ironing: with a fiatiron, great difficulty has been experienced in ironing starched". surfaces due": to an: accumulation or build-up of starch on the ironingsurface of the.- iron: Moreover, when ironingJlinen? cloth, great care must be exercised lest: scorching of the cloth takes place'. Again, when ironing certain:fabrics,.such as rayon,-there is 'a tendency for the iron to drag the rayon so as to pull it: over the ironing pad by the iron.

Several suggestions have been. made for overcoming the abovedifii'culties' encountered in using ffatironsfi Onemetlio'dcomprisestreatingthe surface of the flatiron with oily or waxy materials. Thus, the hot surface of the flatiron has been coated with either wax or mineral oil. In the case of the wax coating, it was found that the degree of slip was improved slightly. The mineral oil additionally improved the degree of slip, but in the case of both the wax and the mineral oil there was a tendency of the lubricating material to decompose and to contaminate the surface of the flatiron. In addition, a great dealof objectionable odors were given off as a result of the decomposition of the mineral oil.

I have now discovered that all the foregoing disadvantages can be obviated by coating the ironing surface of a flatiron with a thin film of a non-thermosetting silicone. By means of my invention, undesirable build-ups of starch are avoided when pressing starched fabrics, scorching of such sensitive materials as linens is materially reduced, and the surface of the flatiron can be caused to slip over rayon fabrics with scarcely any perceptible drag of the latter.

In accordance with my invention, the ironing surface of the flatiron is coated by suitable means with a liquid non-thermosetting silicone or organopolysiloxane. One method comprises wiping the ironing surface of the iron on a cloth or paper (e. g., asbestos) pad impregnated with the aforementioned non-thermosetting silicone. Such pads, which may comprise one layer or a series of superposed layers, may take the form of a heatresistant cloth or paper pad impregnated with any suitable amount of a liquid silicone. It is preferred that the pad be porous and capable of absorbing the silicone in varying amounts.

Among such heat-resistant pads may be men-v tioned various materials, such as asbestos cloth,

The amount of non-thermosetting silicone enfp'loyed maybe varied within wide limitsf depend ing on the absorbin'gsurface used and depending upon the degree ofi'mpregna'tion' desired; Gen"- er'ally'; the heat-resistant, fibrous pad mayonntain from I to 50 e. g'., from 5' to-) or more-per cent, by weight, thereof of the-non-thermo'settihg silicone. Iha've found that an-asbestosclotlr pad impregnated with about '20 per cent, by weight; of i a liquid methylpolysiloxane" has been in continuous use for almost nine months and was still giving satisfactory results-at" the end of such time. In many'inst'ances', it hasbeen found de' sirable to rest the ironing surface of the iron on such a pad during ironing operations. This is the reason that heat-resistant materials" are preferably used with the non-thermosetting silicone. It. will of course be understood that other lessheat-resist'ant'materials; such-ascotton, canvas, etc., may also be employed.

It will, of course, be apparent to those skilled in the art that other methods may be employed for coating the ironing surface of the iron with the non-thermosetting silicone and it is not in- 25 tended that the claimed invention be limited to the method described above. Thus, I may use a silicone rubber containing a small amount of volatile non-thermosetting silicones, as, for instance, organopolysiloxane rubbers of the type disclosed and claimed in Agens Patent 2,448,756, issued September 7, 1948 and assigned to the same assignee as the present invention.

The term silicones herein employed and in the appended claims is intended to mean and include organopolysiloxanes having alternate silicon and oxygen atoms in the skeletal structure, and containing silicon-bonded hydrocarbon radicals. Such hydrocarbon radicals may comprise, for instance, alkyl radicals (e. g., methyl, ethyl, propyl, isobutyl, amyl, decyl, etc.); aryl radicals (e. g., phenyl, napthyl, anthracyl, etc); alkaryl radicals (e. g., tolyl, xylyl, etc.) aralkyl radicals (e. g., benzyl, phenylethyl, etc.) cycloalkyl radicals (e. g., cyclopentyl, cyclohexyl, etc); heterocyclic radicals, etc. stated alternatively, when an alkylpolysiloxane is employed, such material may also bejdentified as an alkylated siloxy composition in which some of the carbon atoms may, if desired, contain phenyl radicals or other organic radicals attached thereto by (3-51 linkages. The hydrocarbon substituent may be substituted with essentially inert substituents as, for example, halogens, etc.

' The usual silicones employed in the practice 55 of my invention generally should be liquid and 50 to 5,000 centistokes have been found to besuitable.

In the choice of the non-thermosetting silicone it has been found preferable in many instances to employ organopolysiloxanes havingan average 7 ratio of, for instance, from about 1.9 to 3.0, especially from 1.95 to 2.5, organic groups per silicon atom. Many such organopolysiloxanes are more. particularly disclosed and claimed in the copending application of Wilcock, Serial No. 656,162

weight, thereof of a methylpolysiloxane in which the methyl groups are attached to the silicon atoms by carbon-silicon linkages, there being present in'the methylpolysiloxane from 1.95 to 2.5 methyl groups per silicon atom, whereby a thin film of the aforesaid methylpolysiloxane is deposited on the hot ironing surface of the flatiron, and thereafter carrying ,out the pressing operation whereby scorching and sticking of clothes during pressing is materially reduced and the passage of the hot iron over the clothes during g the pressing operation is substantially enhanced.

filed March 21, 1946 and Patnode applications Serial Nos, 463,813 and 463,814 filed October 29,1942,- the formerPatnode application now being abandoned and the latter Patnode application now issued as U. 5. 2,469,888, on May. 10, 1949, all the foregoing applications being assigned to the sameassignee as the present inyention. In'general, I prefer to use polymeric methyl siloxanes (methyl silicones), or polymeric methyl phenyl siloxanes -(methyl phenyl silicones)- whose organic substituents are present in the above-mentioned ratio. However, I do not intend to be'limited to these particular silicones 'nor to these particular ratiosof organo groups since, as pointed out previously, other silicones and other ratios of organic groups to silicon atoms may be employed without departing from the scope of the invention. V -What I claim as new and desire to secure by Letters Patent of theUnited States is:'

V I In the process for ironing clothes which may THOMAS. J. RASMUSSEN.

, References Cited in the file of .this patent UNITED STATES PATENTS Number 7 Name Date a 350,966 Barnes Oct-1'9, 1886 586,985 Woisard July 27, 1897 1,455,484 Grenda May '15, 1923 1,647,545 Rocco Nov. 1, 1927 2,377,689 Hyde 1) June 5, 1945 2,384,384 McGreg'or et' a1. Sept. 4, 1945 2,389,216 Smith -Q. NOV. 20,1945 2,432,665 Hyde -(3) Dec. 16, 1947 2,452,254 McGregor et a1. Oct, 26, 1948 2,462,267 Hyde (2) Feb. 22,, 1 949 2,469,888 Patnode MaylO, 1949 OTHER REFERENCES 

